For me depends on how I'm working out, if I'm doing heavy weights I try for 3-4 sets of 8 but might only get 6 on the last 1 or 2 sets. after a warm up set of 21's (7 top half, 7 bottom half, 7 full) at half the weight I use for the other 3 or 4 sets,
But I do a lot of volume training with sets/reps all over the place..

8-12 is probably the best range to build muscle. However, as pointed out below, diet plays the biggest role.

Just curious why you post one time about cutting BF and weight loss and in another post you ask about how to gain weight?!?! Are you just curious or are u deciding on what you want to do? My best answer for you based on questions you asked is to get diet in check 100% and work a little harder in the gym. No matter if its cutting or gaining you will get good results of you do that. I'm just basing this off your questions and stats you posted on previous post.